When booting Puppy 2.01r2 or 2.02, I get the following:
- the boot process stalls
- after about a minute, a Call Trace line appears, followed by nineteen lines of text, each one beginning with an 8-digit hex number enclosed in [< and >]
- the word Code: followed by 64 pairs of hex numbers
- the following line:
<0> Kernel panic - not syncing: Fatal exception in interrupt
- and then I have to push the reset button to get anything else to happen.

In Puppy 2.01r2, this happens after the following line appears in the boot process:
Registering unionfs 20060417-0541

In Puppy 2.02, this happens after the following three lines appear:
Registering unionfs 20060503-0408
fuse init (API version 7.6)
Looking for Puppy in partition hdc (iso9660 filesystem)

The CD-ROMs I am using boot fine in two other machines I have, so they are not suspect.

Another Linux distro that I tried in this particular machine would not boot unless I added "probe=scsi" to the boot command.

I suspect the CD-ROM drive hardware may be contributing to the problem, but I don't know how it would.

OK. First, are all the drives IDE or are there any SCSI drives/controllers? Does anything different happen if you type puppy probe=scsi at the boot prompt, as you mentioned? Since this does sound to be related to your specific hardware, especially with the "Fatal exception in interrupt" error, you might try to see if trying different ACPI options may be related also. See the boot parameter wiki page for more.

I couldn't find anything out about "probe=scsi" in any of the information referred to. I'll have to check the documentation for the other distro to see if possibly its "probe=scsi" boot option does the same thing as "ide=nodma" does for Puppy.

Ted, when you boot Windows on this machine, do you by any chance have a

device=c:\windows\dblbuff.sys

line in config.sys (if you have same) (this line loads the disk cache buffer into low memory, which is guaranteeably DMA-enabled, whereas upper memory is not), and/or do you have a

DoubleBuffer=1

line (which accomplishes the same thing as the dblbuff.sys line) in msdos.sys? I assume the "other" OS is some flavor of Win9x.

You can check without having to open either file for editing, by opening a DOS window and issuing

mem /c | find "dblbuff" /i

and see if a line appears.

I am thinking a little above my experience-level now, that it may be possible to recompile the Linux kernel to specify that the disk cache buffers are loaded low, not high, just as dblbuff does. My theory being, that it is the inconsistency between the request for DMA and the upper memory's lack thereof, and not the DMA request itself, that is the stumbling block. If my theory is correct, then this slight change would greatly speed up both disk and CD access on older hardware such as Ted's.

Ted, when you boot Windows on this machine, do you by any chance have a

device=c:\windows\dblbuff.sys

line in config.sys (if you have same) (this line loads the disk cache buffer into low memory, which is guaranteeably DMA-enabled, whereas upper memory is not), and/or do you have a

DoubleBuffer=1

line (which accomplishes the same thing as the dblbuff.sys line) in msdos.sys? I assume the "other" OS is some flavor of Win9x.

I wiped Win95 off the hard drive about a year ago, so I can't give you a definitive answer based on looking at it right now, but I am just about positive that it was not using double-buffering. I had read an article somewhere that I interpreted to mean that double-buffering was A Bad Thing for my particular PC, so I made sure it didn't have it, but this was so long ago that I can't be absolutely sure.

Thanks for the reply. I'll try it both ways, someday, when I finally learn how to compile the kernel and do so on my own 233MMX.

Actually, my P3-800 Thinkpad T21 does not have upper memory DMA-enabled, either, except for the block at D000-DFFF. I can't help but wonder whether this slows my Puppy disk access. But it isn't a front-burner issue.

You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot vote in polls in this forumYou cannot attach files in this forumYou can download files in this forum